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    <title>Document</title>
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    <div style="font-size: 10px;" onclick="changeSize()">哈哈哈</div>
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    function changeSize(){
        
    let element = document.querySelector("div")
    console.log(element.style)
    let size = parseInt(element.style.fontSize)+10 
    element.style.fontSize = size +"px"

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